Systems have been developed to monitor, for example, vehicle tire pressure, and to report the tire pressure to a receiver at a central monitoring station using radio transmissions. A typical remote automotive tire pressure monitoring system includes a plurality of tire-based sensory transmitters and a central, vehicle-based arrangement. The sensory transmitters include a component that senses a tire condition, such as tire pressure or tire temperature. Each transmitter is capable of outputting a coded transmission that conveys sensed tire condition information and an identifier for reception by the vehicle-based arrangement. Within the vehicle-based arrangement, an electronic control unit (“ECU”) processes the conveyed information and controls provision of information regarding the sensed tire conditions to a vehicle operator.
During assembly and routine maintenance such as tire rotation or tire replacement, the tire pressure monitoring system must be calibrated. Calibration involves associating the various tire positions with the pressure transmitters that are located on the tires. One proposed method for calibrating a system uses a magnet device to initiate the calibration. In this system, an internal vehicle display panel with locations corresponding to the tire location is activated. When the tire locations are illuminated on the display, the vehicle operator or service technician places the magnet near the indicated tire. The transmitter then sends a code corresponding thereto to the central controller. When the indicator indicates another tire location, the magnet must be brought near each tire location until each of the tire locations have a tire registered thereto. One problem with this device is that a separate component such as a magnet must be provided to the vehicle operator that is used only in the calibration process. One problem associated with a separate magnet device is that such a device is subject to loss. Thus, the tire pressure monitoring system would be rendered inoperable.
There is a need for a tire pressure monitoring system that conveniently provide tire pressure information to a technician during assembly and routine maintenance of tires. Also, there is a need for a tire pressure monitoring system that efficiently provide tire pressure information to a technician in order to reduce amount of time for maintenance of tires.